Device for unscrewing and drawing pipes



6. V. LEWIS.

DEVICE FOR UNSCREWING AND DRAWING PIPES.

APPLICATION FILED SEPT,27, 192i.

Patented J 11 110 20,

J em? v. LEWIS, or nons'ron", rams.

DEWQE FQR VN'SCREWING AND DWING PIPEQ.

man.

To all whom it may concern: Be it known that I, GUY V. LEWIS, a citizen of the United States, residing at Houston, in the county of Harris and State of Texas, have invented certain new and useful Improvements in a Device for Unscrewing and Drawing Pipes, of which thefollowingis a specification.

This invention relates-to new and useful improvements in a device for unscrewing and drawing pipe.

The object of the invention is to provide a device of the character described by means of which joints of pipe which have become stuck in a well bore may be unscrewed" and separated and withdrawn from the bore.

In drilling oil and other wells, the pipe often becomes stuck in the bore and it sometimes becomes impossible to withdraw the entire string at one time, in which case it becomes necessary to backoif or'unscrew one or more joints at a time to withdraw the entire string. The joints of pipe in most common use are right hand threaded and in backing ofi or unscrewing the joints, a string of pipe having left hand threads must be employed to the lower end, of which a fishing tool is attaclred which engages with the upper section of the string being withdrawn to unscrew the same. This necessitates keeping on hand a'string of pipe having left hand threads which adds considerable expense to drilling operations, It is the object of this invention to provide a device by means of which the joints of the string to be withdrawn may be backed ofl or unscrewed without the necessity of maintaining a string of left hand threaded pipe, the device herein described being much lighter, simpler and cheaper than means now commonly employed for a similar purpose.

With the above and other objects in view,

the invention has particular relation to certain novel features of constructlon, operatlon and arrangement of parts an example of which is given in this speci cation and illustrated in the accompanying drawings, where-- Qpecification of Letters IPatent. Patent'cggqi J 2Q) 1922 Application filed September 27, 1921. Serial No. 503,691.

figures, the numeral 1, refers to a cup shapedcasing, having a cap 2, threaded thereon. The casing has a bearlng 3, through its lower end, and the cap is provided with an aligned bearing 4:, and rotatably mounted in these bearings are the stems 5 and 6. These stems have the discs? and 8, respectively, fixed thereon, interposed between which and the ad acent bearings 3 and 4 are anti-friction rollers, provided for the usual purpose. Underneath the bearing 3 is'a collar 9, which s fixed upon the stem 5, and above the bearing 4 1s a similar collar 10, fixed upon the stem 8. EV this construction, the stems 5 and are xed against endwise movement. The inner ends of the stems 5 and 6 have the bevel gear wheels 11 and 12, respectively, fixed thereon. These gear wheels are spaced apart and are in mesh with the pinions 13, which are located between them, and which are rotatable upon suitable spindles, pro- JBCtlIjlg inwardly from the wall of the easing In operation, the stem 6 is rotated from the pipe 14:, which is connected to the upper through the bevel gear wheels 11 and 12, and

the pinions 13, to the stem 5, which will thereby be rotated in the opposite direction.

The lower end of thestem 5 carries a fishing tool 16, which engages with the pipe 17,

to be withdrawn, and it is obvious that when the fishing tool en ages with the upper joint of said pipe 17, t e same will be backed off or unscrewed and may then be withdrawn.

The discs 7 and 8 and the collars 9 and 10, sustain the end thrust imparted by the stems 5 and 6, and thus protect the bevel gear wheels 11 and 12, and the intermediate pinions 13.

What I claim is:

1 A device of the character described, in-

eluding a casing, adapted to be let down into' a well, relatively rotatable members operating in bearings therein, bevel gear wheels rotatable inions anchored to theeasing, and interpose between and in mesh with said gear Wheels, and means for fixing the casing against rotation in the well.

2. A device for unscrewing pipe in a Well, includin a casing, adapted to be let down into sai well, a shaft, having a bearingin said casing, a fishing tool carried by the lower end of said shaft and adapted to enage with the pipe to be unscrewed,a cap fitted onto said casing and inclosin'g the same, said cap being provided with a bearing, a shaft rotatable 1n said last mentioned bearing, means for rotating said last mentioned shaft, bevel gear wheels fixed upon the adjacent ends of said shafts, pinions anchored to the casing and located between and in mesh with said bevel gear wheels, and dogs carried by the casing, and adapted to engage with the walls of the well to fix the casing against turning therein. 7

In testimony whereof I have signed my name to this specification in the presence of two subscribingwitnesses.

' GUY V. LEWIS. Witnesses:

WM. A. (JATHEY. 

